Summary: Normally when you do a bitwise operation on an enum value, you
get back an instance of the underlying type (e.g. int). But using this
macro, bitwise ops on your enum will return you back instances of the
enum. This is particularly useful for enums which represent a
combination of flags.
Suppose you have a function which takes an int and a set of flags. One
way to do this would be to take two numeric params:
enum SomeFlags { F1 = 1, F2 = 2, F3 = 4, ... };
void Fn(int Num, int Flags);
void foo() {
Fn(42, F2 | F3);
}
But now if you get the order of arguments wrong, you won't get an error.
You might try to fix this by changing the signature of Fn so it accepts
a SomeFlags arg:
enum SomeFlags { F1 = 1, F2 = 2, F3 = 4, ... };
void Fn(int Num, SomeFlags Flags);
void foo() {
Fn(42, static_cast<SomeFlags>(F2 | F3));
}
But now we need a static cast after doing "F2 | F3" because the result
of that computation is the enum's underlying type.
This patch adds a mechanism which gives us the safety of the second
approach with the brevity of the first.
enum SomeFlags {
F1 = 1, F2 = 2, F3 = 4, ..., F_MAX = 128,
LLVM_MARK_AS_BITMASK_ENUM(F_MAX)
};
void Fn(int Num, SomeFlags Flags);
void foo() {
Fn(42, F2 | F3); // No static_cast.
}
The LLVM_MARK_AS_BITMASK_ENUM macro enables overloads for bitwise
operators on SomeFlags. Critically, these operators return the enum
type, not its underlying type, so you don't need any static_casts.
An advantage of this solution over the previously-proposed BitMask class
[0, 1] is that we don't need any wrapper classes -- we can operate
directly on the enum itself.
The approach here is somewhat similar to OpenOffice's typed_flags_set
[2]. But we skirt the need for a wrapper class (and a good deal of
complexity) by judicious use of enable_if. We SFINAE on the presence of
a particular enumerator (added by the LLVM_MARK_AS_BITMASK_ENUM macro)
instead of using a traits class so that it's impossible to use the enum
before the overloads are present. The solution here also seamlessly
works across multiple namespaces.
[0] http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20150622/283369.html
[1] http://lists.llvm.org/pipermail/llvm-commits/attachments/20150623/073434b6/attachment.obj
[2] https://cgit.freedesktop.org/libreoffice/core/tree/include/o3tl/typed_flags_set.hxx
Reviewers: chandlerc, rsmith
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D22279
llvm-svn: 275292
re-insertion of entries into the worklist moves them to the end.
This is fairly similar to a SetVector, but helps in the case where in
addition to not inserting duplicates you want to adjust the sequence of
a pop-off-the-back worklist.
I'm not at all attached to the name of this data structure if others
have better suggestions, but this is one that David Majnemer brought up
in IRC discussions that seems plausible.
I've trimmed the interface down somewhat from SetVector's interface
because several things make less sense here IMO: iteration primarily.
I'd prefer to add these back as we have users that need them. My use
case doesn't even need all of what is provided here. =]
I've also included a basic unittest to make sure this functions
reasonably.
Differential Revision: http://reviews.llvm.org/D21866
llvm-svn: 274198
a sequence of values.
It increments through the values in the half-open range: [Begin, End),
producing those values when indirecting the iterator. It should support
integers, iterators, and any other type providing these basic arithmetic
operations.
This came up in the C++ standards committee meeting, and it seemed like
a useful construct that LLVM might want as well, and I wanted to
understand how easily we could solve it. I suspect this can be used to
write simpler counting loops even in LLVM along the lines of:
for (int i : seq(0, v.size())) {
...
};
As part of this, I had to fix the lack of a proxy object returned from
the operator[] in our iterator facade.
Differential Revision: http://reviews.llvm.org/D17870
llvm-svn: 269390
This is a recommit of r264414 after fixing the buildbot failure caused by
incompatible use of std::vector.erase().
The original message:
Add erase() which returns an iterator pointing to the next element after the
erased one. This makes it possible to erase selected elements while iterating
over the SetVector :
while (I != E)
if (test(*I))
I = SetVector.erase(I);
else
++I;
Reviewers: qcolombet, mcrosier, MatzeB, dblaikie
Subscribers: dberlin, dblaikie, mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D18281
llvm-svn: 264450
Summary:
Add erase() which returns an iterator pointing to the next element after the
erased one. This makes it possible to erase selected elements while iterating
over the SetVector :
while (I != E)
if (test(*I))
I = SetVector.erase(I);
else
++I;
Reviewers: qcolombet, mcrosier, MatzeB, dblaikie
Subscribers: dberlin, dblaikie, mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D18281
llvm-svn: 264414
MSVC as usual:
C:\Buildbot\Slave\llvm-clang-lld-x86_64-scei-ps4-windows10pro-fast\llvm.src\include\llvm/ADT/STLExtras.h(120):
error C2100: illegal indirection
C:\Buildbot\Slave\llvm-clang-lld-x86_64-scei-ps4-windows10pro-fast\llvm.src\include\llvm/IR/Instructions.h(3966):
note: see reference to class template instantiation
'llvm::mapped_iterator<llvm::User::op_iterator,llvm::CatchSwitchInst::DerefFnTy>'
being compiled
This reverts commit e091dd63f1f34e043748e28ad160d3bc17731168.
llvm-svn: 263760
type.
This makes it easy and safe to use a set of flags as one elmenet of
a tagged union with pointers. There is quite a bit of code that has
historically done this by casting arbitrary integers to "pointers" and
assuming that this was safe and reliable. It is neither, and has started
to rear its head by triggering safety asserts in various abstractions
like PointerLikeTypeTraits when the integers chosen are invariably poor
choices for *some* platform and *some* situation. Not to mention the
(hopefully unlikely) prospect of one of these integers actually getting
allocated!
With this, it will be straightforward to build type safe abstractions
like this without being error prone. The abstraction itself is also
remarkably simple thanks to the implicit conversion.
This use case and pattern was also independently created by the folks
working on Swift, and they're going to incrementally add any missing
functionality they find.
Differential Revision: http://reviews.llvm.org/D15844
llvm-svn: 257284
This is a much more general and powerful form of PointerUnion. It
provides a reasonably complete sum type (from type theory) for
pointer-like types. It has several significant advantages over the
existing PointerUnion infrastructure:
1) It allows more than two pointer types to participate without awkward
nesting structures.
2) It directly exposes the tag so that it is convenient to write
switches over the possible members.
3) It can re-use the same type for multiple tag values, something that
has been worked around by either abusing PointerIntPair or defining
nonce types and doing unsafe pointer casting.
4) It supports customization of the PointerLikeTypeTraits used for
specific member types. This means it could (in theory) be used even
with types that are over-aligned on allocation to expose larger
numbers of bits to the tag.
All in all, I think it is at least complimentary to the existing
infrastructure, and a strict improvement for some use cases.
Differential Revision: http://reviews.llvm.org/D15843
llvm-svn: 257282
This reverts commit r243567, which ultimately reapplies r243563.
The fix here was to use std::enable_if for overload resolution. Thanks to David
Blaikie for lots of help on this, and for the extra tests!
Original commit message follows:
For cases where we needed a foreach loop in reverse over a container,
we had to do something like
for (const GlobalValue *GV : make_range(TypeInfos.rbegin(),
TypeInfos.rend())) {
This provides a convenience method which shortens this to
for (const GlobalValue *GV : reverse(TypeInfos)) {
There are 2 versions of this, with a preference to the rbegin() version.
The first uses rbegin() and rend() to construct an iterator_range.
The second constructs an iterator_range from the begin() and end() methods
wrapped in std::reverse_iterator's.
Reviewed by David Blaikie.
llvm-svn: 243581
This reverts commit r243563.
The GCC buildbots were extremely unhappy about this. Reverting while
we discuss a better way of doing overload resolution.
llvm-svn: 243567
For cases where we needed a foreach loop in reverse over a container,
we had to do something like
for (const GlobalValue *GV : make_range(TypeInfos.rbegin(),
TypeInfos.rend())) {
This provides a convenience method which shortens this to
for (const GlobalValue *GV : reverse(TypeInfos)) {
There are 2 versions of this, with a preference to the rbegin() version.
The first uses rbegin() and rend() to construct an iterator_range.
The second constructs an iterator_range from the begin() and end() methods
wrapped in std::reverse_iterator's.
Reviewed by David Blaikie.
llvm-svn: 243563
`LLVM_ENABLE_MODULES` builds sometimes fail because `Intrinsics.td`
needs to regenerate `Instrinsics.h` before anyone can include anything
from the LLVM_IR module. Represent the dependency explicitly to prevent
that.
llvm-svn: 239796
If the template specialization for externally managed sets in
PostOrderIterator call too far out of sync with each other, this unit
test will fail to build. This is especially useful for developers who
may not build Clang (the only in-tree user) every time.
llvm-svn: 222447
A subtle bug was found where attempting to copy a non-const function_ref
lvalue would actually invoke the generic forwarding constructor (as it
was a closer match - being T& rather than the const T& of the implicit
copy constructor). In the particular case this lead to a dangling
function_ref member (since it had referenced the function_ref passed by
value to its ctor, rather than the outer function_ref that was still
alive)
SFINAE the converting constructor to not be considered if the copy
constructor is available and demonstrate that this causes the copy to
refer to the original functor, not to the function_ref it was copied
from. (without the code change, the test would fail as Y would be
referencing X and Y() would see the result of the mutation to X, ie: 2)
llvm-svn: 221753
Previously, the assertions in PointerIntPair would try to calculate the value
(1 << NumLowBitsAvailable); the inferred type here is 'int', so if there were
more than 31 bits available we'd get a shift overflow.
Also, add a rudimentary unit test file for PointerIntPair.
llvm-svn: 203273
The interaction between defaulted operators and move elision isn't
totally obvious, add a unit test so it doesn't break unintentionally.
llvm-svn: 202662
it interoperate (minimally) with std::unique_ptr<T>. This is part of my
plan to migrate LLVM to use std::unique_ptr with a minimal impact on
out-of-tree code.
Patch by Ahmed Charles with some minor cleanups (and bool casts) by me.
llvm-svn: 202608
unique ownership smart pointer which is *deep* copyable by assuming it
can call a T::clone() method to allocate a copy of the owned data.
This is mostly useful with containers or other collections of uniquely
owned data in C++98 where they *might* copy. With C++11 we can likely
remove this in favor of move-only types and containers wrapped around
those types.
llvm-svn: 194315
This generalizes Optional to require less from the T type by using aligned
storage for backing & placement new/deleting the T into it when necessary.
Also includes unit tests.
llvm-svn: 175580
A SparseMultiSet adds multiset behavior to SparseSet, while retaining SparseSet's desirable properties. Essentially, SparseMultiSet provides multiset behavior by storing its dense data in doubly linked lists that are inlined into the dense vector. This allows it to provide good data locality as well as vector-like constant-time clear() and fast constant time find(), insert(), and erase(). It also allows SparseMultiSet to have a builtin recycler rather than keeping SparseSet's behavior of always swapping upon removal, which allows it to preserve more iterators. It's often a better alternative to a SparseSet of a growable container or vector-of-vector.
llvm-svn: 173064
for this class. These tests exercise most of the basic properties, but
the API for TinyPtrVector is very strange currently. My plan is to start
fleshing out the API to match that of SmallVector, but I wanted a test
for what is there first.
Sadly, it doesn't look reasonable to just re-use the SmallVector tests,
as this container can only ever store pointers, and much of the
SmallVector testing is to get construction and destruction right.
Just to get this basic test working, I had to add value_type to the
interface.
While here I found a subtle bug in the combination of 'erase', 'begin',
and 'end'. Both 'begin' and 'end' wanted to use a null pointer to
indicate the "end" iterator of an empty vector, regardless of whether
there is actually a vector allocated or the pointer union is null.
Everything else was fine with this except for erase. If you erase the
last element of a vector after it has held more than one element, we
return the end iterator of the underlying SmallVector which need not be
a null pointer. Instead, simply use the pointer, and poniter + size()
begin/end definitions in the tiny case, and delegate to the inner vector
whenever it is present.
llvm-svn: 161024
Makefiles, the CMake files in every other part of the LLVM tree, and
sanity.
This should also restore the output tree structure of all the unit
tests, sorry for breaking that, and thanks for letting me know.
The fundamental change is to put a CMakeLists.txt file in the unittest
directory, with a single test binary produced from it. This has several
advantages:
- No more weird directory stripping in the unittest macro, allowing it
to be used more readily in other projects.
- No more directory prefixes on all the source files.
- Allows correct and precise use of LLVM's per-directory dependency
system.
- Allows use of the checking logic for source files that have not been
added to the CMake build. This uncovered a file being skipped with
CMake in LLVM and one in Clang's unit tests.
- Makes Specifying conditional compilation or other custom logic for JIT
tests easier.
It did require adding the concept of an explicit 'optional' source file
to the CMake build so that the missing-file check can skip cases where
the file is *supposed* to be missing. =]
This is another chunk of refactoring the CMake build in order to make it
usable for other clients like CompilerRT / ASan / TSan.
Note that this is interdependent with a Clang CMake change.
llvm-svn: 158909
Justin Lebar